1. Technical Field
The present invention relates generally to gas turbine engines and, in particular, to a fan assembly that includes one or more energy absorbent fan blade spacers.
2. Background Information
A fan assembly for a typical gas turbine engine includes a plurality of fan blades arranged circumferentially around a rotor disk. Each fan blade may include an airfoil connected to a dovetail root, which is inserted into a respective dovetail slot within the rotor disk. The radial height of the root is typically less than the radial height of the slot. A gap therefore may be farmed between a radial inner surface of the root and a radial inner surface of the slot. Such a gap is typically filled with a fan blade spacer.
A typical fan blade spacer reduces slippage and wear between the root and the slot during engine operation when, for example, centrifugal loading on the fan blade is relatively low (e.g., during wind milling). The fan blade spacer may be configured therefore to reduce (e.g., minimize) clearance within the gap that would otherwise be available for relative motion (e.g., pivoting) between the root and the slot. Such a rigid connection between the rotor disk and the fan blade, however, may increase internal strains on the fan blade when, for example, an object (e.g., a bird or a released fan blade) collides with the fan blade.